Jiaodong Peninsula refers to the Shandong Peninsula area east of Jiaolai Valley or Jiaowei Plain.
Jiaodong in a narrow sense refers to Yantai, Weihai and Qingdao, and in a broad sense includes Rizhao and Weifang.
Jiaodong Peninsula is located in the northeast coastal area of China's North China Plain, in the hilly area in the east of Shandong Province, with the latitude of 35 35 ′-38 23 ′ north and the longitude of119 30 ′-122 42 ′ east. The Bohai Sea is in the north, the Yellow Sea is opposite to Liaodong Peninsula, and Huang Haidong faces the Korean Peninsula and Japanese archipelago across the sea, with a total land area of 30,000 square kilometers, accounting for 19% of Shandong Province. Jiaodong Peninsula belongs to Jiaoliao Tailong, a quasi-platform of China and Korea. Archaean gneiss, schist and other deep metamorphic crystalline rocks are widely exposed, and there are extensive volcanic eruptions and acidic magma intrusions at the end of Cretaceous. After Miocene, Bohai Sea generally subsided to a great extent, becoming the largest Cenozoic faulted basin with the deepest subsidence zone in North China-Lower Liaohe River. At the end of Pliocene, especially since Quaternary, the Bohai Strait was fractured and subsided, and Shandong Peninsula was formed. The whole area is divided by two sets of faults, namely, NNE and NNW, forming fault blocks with different sizes. After long-term erosion and division, relatively broken low hills are formed. Several mountains stand out above the mountains. In the south of the peninsula, the elevation of the old peak of Laoshan Mountain is 1 133 meters, which is the highest peak in the peninsula. Yashan, Kunyu Mountain, Wade, Luoshan, Daze Mountain, Ai Shan, etc. In the north-central part, most of them are northeast. There are Taocun Graben Basin, Laiyang Fault Basin and Jiaolai Depression Plain among the mountains. There are strip plains with different widths along the coast, and the Peng (Lai) Huang (County) Ye (County) Plain has the largest area.
The coast of Jiaodong Peninsula twists and turns, and the gulf islands crisscross, which is a concentrated area of good ports along the coast of North China. Qingdao in Jiaozhou Bay, Yantai in Zhifu Bay, Weihai in Weihai Bay, Shidao and Longkou in Shidao Bay are all northern ports in China. The sand mouth beach on the peninsula is developed. Where sandbars are developed, islands are connected with land, forming land-connected islands, such as Zhifu Island near Yantai and Qie Island near Longkou. Island. Except miaodao islands in the Bohai Strait, the coastal islands are all distributed in the coastal zone, and the larger ones are Elephant Island, Mayang Island, Mo Xie Island, Dujia Island, Tian Heng Island, Liu Gongdao Island, Jiming Island, Kongtong Island, Chu Island, Sushan Island and Nanhuangdao. Jiaodong Peninsula has a warm temperate humid monsoon climate. The average temperature of 1 month is -3℃ to-1℃, the average temperature in August (the hottest month) is about 25℃, and the extreme maximum temperature is about 38℃. The active accumulated temperature above 10℃ is 3800-4 100℃. The annual precipitation is 650-850 mm, more than 800 mm on the south side of the peninsula; The northwest coastal plain is about 600 mm, and about 60% of the annual precipitation is concentrated in summer, with high intensity and frequent rainstorm. The annual relative variability of precipitation is about 20%. The annual average relative humidity is above 70%. The southern coast on the east side of the peninsula is foggy from April to July, with an average annual foggy day of 30-50 days.
Water system Peninsula water system originated in the central mountainous area, divided into north and south, and went into the sea alone. The river bed is relatively large, and the source is short and fast. There is a big gap between drought and flood in river runoff, and 70%-80% of the annual runoff is concentrated in flood season. Water level and discharge hydrograph fluctuate rapidly with the change of precipitation, but they are generally harmless. In case of rainstorm, mountain torrents will occur, and the estuary will be supported by tides, which will often aggravate the flood hazard; In the dry season, the riverbed is exposed, and the river is cut off in autumn, winter and spring.
Vegetation and soil natural vegetation is warm temperate deciduous broad-leaved forest, and the main tree species are Quercus, such as Quercus acutissima and Castanopsis fissa. Among them, Quercus acutissima is the most abundant, but due to the stocking of tussah, the trunk is often cut off in a shrub shape, which constitutes a special "tussah orchid" landscape in mountainous hills. Conifers are represented by Japanese red pine. There are subtropical elements in the flora, such as bitter wood, mountain pepper, mountain pepper and so on. There are also flora elements in Northeast China, such as Quercus mongolica, Quercus liaotungensis and Populus davidiana. At the beginning of the 20th century, black pine and Japanese larch were introduced. Shandong Peninsula has a long history of development, and the native plants have been completely destroyed.
Zonal soil is a typical brown forest soil (commonly known as Shandong brown soil), which is generally distributed on gentle slopes and well-drained flat land. Most of it has been transformed into farmland and orchards, and it is a mature cultivated soil. The coarse bone brown soil on the residual slope deposits in the middle and upper parts of low hills is shallow and rough in texture, and many crops such as peanuts and sweet potatoes are planted. Apples, pears, grapes and cherries are the main fruit trees in the peninsula. The famous ones are Yantai apples, Laiyang pears, Pingdu Dazeshan grapes and Rushan Zhongjiagou cherries.